Advances in Epidemiology, Biology and Laboratory Diagnosis of Zika Virus

Zika virus (ZIKV) was spread to both eastward and westward from Uganda where the virus was identified approximately in 1947 by a group of arbovirus researchers. In 2015, ZIKV reached Americas with major outbreaks in Brazil. Most countries with mosquito transmitted ZIKV infection are located in tropical and subtropical areas, where ZIKV is endemic with other flaviviruses, including JEV, dengue and yellow fever virus. Approximately 40 countries in Central and South Americas and territories in South Pacific Islands and South East Asia show autochthonous ZIKV endemics. American lineage of ZIKV is known significantly to be mutated in susceptibility to host and in pathogenicity from Asian and Asian lineages approximately since 2014. Early and specific identification of ZIKV infection is very important for the effective management of patients. First of all, optimal collection of specimens for the laboratory diagnosis is required for both nucleic acid testing (NAT) and serological tests. Specimens for NAT tests and serological tests should be determined by the available laboratory resources, work-flow in each laboratory and the geographic areas of specimen collected in addition to days after showing symptoms. Testing strategy for specific differentiation among flaviviruses will vary depending on the prevalence of viruses known to be circulating in the area where the patients were exposed. NAT will be employed for the patients presenting with onset of symptoms less than 7 days. Advanced diagnostic technologies should be continuously developed for the increase of specificity and sensitivity of ZIKV diagnosis.

Probiotics Used for Respiratory Diseases

Continuous increase of bacterial resistance to antibiotics causes many problems such as the advent of resistance to pathogenic bacteria, difficulty of microbial disease treatments, environmental pollution and others. It is inevitable to find potential substitutes for antibiotics in order to solve the above mentioned problems. Recently many literatures have shown that probiotics could be applied to the treatment or amelioration of respiratory diseases in addition to intensively studied gut related diseases. Target diseases for collecting data and analysis of the efficacies were chosen because viral respiratory infections are the most common diseases in humans. They were mainly viral diseases like common colds, pneumonia in addition to allergies and asthma. Papers on clinical efficacies, safety risks and mechanisms of microbial action of respiratory diseases were secured through known information sites and analyzed for their exact evaluations. The present analysis of research results on probiotics efficacies for respiratory diseases showed discrepancies in efficacies. On the whole, half to one third of papers reviewed only showed certain level of efficacies against respiratory viral diseases. It is very difficult to compare the results directly because the studies varied highly in study design, outcome measures, probiotics, dose, and matrices used. However, the results obtained so far show the potential applications of probiotics to the prevention or amelioration of the diseases. Conclusively, further well organized studies using randomized, double-blind, placebo-controlled clinical trials are needed to elucidate the realities of probiotics on respiratory related diseases and to obtain more definite efficacy results.

Study on Detection, Isolation and Identifications of Infectious Viruses in Various Water Samples

Various factors using cell lines can effect kinds and frequencies of infectious viruses obtained in the detection tests on various water samples. We tried to find out technical problems for the maximum virus isolations from water samples and characterize the virus isolates from waters in nature and in various purification stages. Fourteen viruses were isolated from 169 water samples by virus monitoring protocol for the information collection requirements rule, US EPA. The morphological changes caused by viruses and mycoplasma infections were compared with for increasing the specificity of tests employed. Cytopathic effects of slow growing viruses were found very similar with those by toxic effects in water samples and mycoplasma infections. Five of 6 stream water samples tested (83.33%) showed virus contaminations with the range of 1.03 to 5.75 MPNs/100 liter. Eight of 24 source water samples (33.35%) showed viral contaminations. One water sample of 24 water samples during precipitation stages was shown to include infectious viruses. It was confirmed that infectious viruses were significantly decreased by purification stages from streams. The titers (TCID50) of virus isolates were ranged as 10(-6.8) ~ 10(-6.925)/ml. The virus isolates were identified by immune fluorescent antibody (IFA) method using virus specific immune sera and serotyped using serotype specific reference sera. Of 14 virus isolates, 7 samples were identified as poliovirus and the other 7 were identified as coxsakie virus. Of 7 polioviruses, one was serotyped as type I, 3 viruses as type II and another 3 as type III. Conclusively, BGM cell lines must be free of mycoplasma for the strict examination of infectious viruses in water and highly sensitive for mainly enteroviruses. In addition, most of infectious viruses showing typical cytopathic effect from water samples were confirmed as coxsackie B and live attenuated vaccine strains of 3 polio types when BGM cells were used for virus isolations.